People who are bad with numbers often find it harder to make ends meet

Math is a skill that some people cannot learn, although they can often do well with a calculator or other aids. They have to be taught differently.

With adequate training to work around this, they can do quite well. However, we are conditioned to think that people who cannot do math are dumb or lazy.

Source: family member taught learning disabled children in schools for many years, until they signed on to the ideology that all children are the same and should be taught the same.